In wireless networks, data is communicated between devices using packets of information which are conveyed through frames. The frame includes a header, which identifies the source and destination addresses and potentially other PHY settings, and a data payload. Additionally, for the purpose of frame detection and timing synchronization, each frame begins with a specific pattern of symbols that is known for the receiver. This specific pattern of symbols may be referred to as a preamble, although other terms may also be used.
As a network device receives a frame, it continuously compares the incoming data stream with the known pattern.
To guarantee successful detection and timing synchronization, the preamble should be sufficiently long. However, this poses a challenge for wireless devices with a limited power source. Many devices in current wireless networks either rely on scarce energy resources, such as small batteries, or harvest energy from the environment.
A long preamble may be problematic because every frame that the wireless devices transmits must start with this preamble. Thus, the longer the preamble, the more energy is consumed. In contrast, a short preamble may make reliable identification of the preamble problematic.
Therefore, it would be advantageous to find a system and method to determine the length of the preamble to maximize energy efficiency without compromising frame detection capabilities at the receiver. Further, it would be beneficial if there were a system and method to determine an optimal detection threshold to maximize the likelihood of correctly detecting the preamble.